The KDIGO guidelines propose a new approach to diagnose chronic kidney disease (CKD) based on estimated glomerular ®ltration rate (GFR). In patients with a GFR value comprised between 45 and 59 mL/ min/1 ... [more ▼]

The KDIGO guidelines propose a new approach to diagnose chronic kidney disease (CKD) based on estimated glomerular ®ltration rate (GFR). In patients with a GFR value comprised between 45 and 59 mL/ min/1.73m2 as estimated by the CKD-EPI creatinine equation (eGFRcreat), it is suggested to con®rm the diagnosis with a second estimation using the CKD-EPI cystatin C-based equations (eGFRcys/eGFRcreat-cys). We sought to determine whether this new diagnostic strategy might extend to kidney transplant recipients (KTR) and help to identify those with decreased GFR. In 670 KTR for whom a measured GFR was available, we simulated the detection of CKD using the two-steps approach recommended by the guidelines in comparison to the conventional approach relying on creatinine equation. One hundred forty-®ve patients with no albuminuria had eGFRcreat between 45 and 59 mL/ min/1.73m2. Among them, 23% had inulin clearance over 60 mL/min/1.73m2 and were thus incorrectly classi®ed as CKD patients. When applying the Kidney Disease: Improving Global Outcomes (KDIGO) strategy, 138 patients were con®rmed as having a GFR below 60 mL/min with eGFRcreat-cys. However, 21% of them were misclassi®ed in reference to measured GFR. Our data do no not support the use of cystatin C as a con®rmatory test of stage 3A CKD in KTR. [less ▲]